Upon discharge, Mancini entered the music industry. In 1946, he became a pianist and arranger for the newly re-formed Glenn Miller Orchestra, led by Tex Beneke. After World War II, Mancini broadened his composition, counterpoint, harmony and orchestration skills during studies with two acclaimed “serious” concert hall composers, Ernst Krenek and Mario Castelnuovo-Tedesco.[2]

Mancini had experience with acting and voice roles. In 1994 he made a one-off cameo appearance in the first season of the sitcom series Frasier, as a call-in patient to Dr. Frasier Crane’s radio show. Mancini voiced the character Al, who speaks with a melancholy drawl and hates the sound of his own voice, in the episode “Guess Who’s Coming to Breakfast?”[6] Mancini also had an uncredited performance as a pianist in the 1967 movie Gunn, the movie version of the series Peter Gunn, the score of which was originally composed by Mancini himself.

Mancini died of pancreatic cancer in Los Angeles. He was working at the time on the Broadway stage version of Victor/Victoria, which he never saw on stage. At the time of his death, Mancini was married to his only wife of 43 years, singer Virginia “Ginny” O’Connor, with whom he had three children. They met while both were members of the Tex Beneke orchestra just after World War II. In 1984, Ginny was one of the founders of the Society of Singers, a non-profit organization which benefits the health and welfare of professional singers worldwide. Additionally the Society awards scholarships to students pursuing an education in the vocal arts. One of Mancini’s twin daughters, Monica Mancini, is a professional singer; her sister Felice runs the The Mr. Holland’s Opus Foundation (MHOF). Son Christopher is a music publisher and promoter in Los Angeles.

In 1996, the Henry Mancini Institute, an academy for young music professionals, was founded byJack Elliott in Mancini’s honor, and was later under the direction of composer-conductor Patrick Williams. By the mid 2000s, however, the institute could not sustain itself and closed its doors on December 31, 2006. However, the American Society of Composers, Authors and Publishers (ASCAP) Foundation “Henry Mancini Music Scholarship” has been awarded annually since 2001. While still alive, Henry created a scholarship at UCLA and the bulk of his library and works are archived in the highly esteemed music library at UCLA.

In 2005, the Henry Mancini Arts Academy was opened as a division of the Lincoln Park Performing Arts Center. The Center is located in Midland, Pennsylvania, minutes away from Mancini’s hometown of Aliquippa. The Henry Mancini Arts Academy is an evening-and-weekend performing arts program for children from pre-K to grade 12, with some classes also available for adults. The program includes dance, voice, musical theater, and instrumental lessons.

Mancini was nominated for an unprecedented 72 Grammys, winning 20.[7] Additionally he was nominated for 18 Academy Awards, winning four.[8] He also won a Golden Globe Award and was nominated for two Emmys.

Mancini won a total of four Oscars for his music in the course of his career. He was first nominated for an Academy Award in 1955 for his original score of The Glenn Miller Story, on which he collaborated with Joseph Gershenson. He lost out to Adolph Deutsch and Saul Chaplin‘s Seven Brides for Seven Brothers. In 1962 he was nominated in the Best Music, Original Song category for “Bachelor in Paradise” from the film of the same name, in collaboration with lyricistMack David. That song did not win. However, Mancini did receive two Oscars that year: one in the same category, for the song “Moon River” (shared with lyricist Johnny Mercer), and one for “Best Music, Scoring of a Dramatic or Comedy Picture” for Breakfast at Tiffany’s. The following year, he and Mercer took another Best Song award for “Days of Wine and Roses“, another eponymous theme song. His next eleven nominations went for naught, but he finally garnered one last statuette working with lyricist Leslie Bricusse on the score for Victor/Victoria, which won the “Best Music, Original Song Score and Its Adaptation or Best Adaptation Score” award for 1983. All three of the films for which he won were directed by Blake Edwards. His score for Victor/Victoria was adapted for the 1995 Broadway musical of the same name.

Le Jazz Hot from the movie Victor/Victoria, performed by Julie Andrews

On April 13, 2004 the United States Postal Service honored Mancini with a 37 cent commemorative stamp. The stamp shows Mancini conducting with a list of some of his most famous movies and TV show themes in the background. The stamp is Scott catalog number 3839.